Process for the production of hydroxylammonium chloride



' duction of hydroxyl Fatented May 2%, m5

Wires 1 PA'raNr orFic 2,377,193 PROCESS FOR THE PRODUCTION OFBOXYLAMIHONIUM CHLO RIDE Philip F. Tryon, Ten-e Haute, Ind., assignor toCommercial Solvents Corporation, Terre Haute, Ind., a corporation ofMaryland No Drawing. Application October 9, 1943,

- Serial No. 505,864

Claims. (01. 23-117) My invention relates to a process for theproduction of hydroxylammonium chloride.. More particularly, it relatesto a process for the procedures utilized, and the comparatively lowyields 10 obtained thereby. Typical of the former methods employed in ths chloride, is the procedure involving the use of sodium nitrite, sodiumbisulflte and sulfur dioxide onium chloride by the reaction of hydroxylm u onium sulfate with hydros thesis of hydroxylammonium and used as thesourceof solvent for another reaction solution. The crystals obtainedfrom this process are preferably dried for approximately two hours atIO-80 C.

The reaction is effected with satisfactory resuits without the presenceof a lower alcohol solvent. However, slightly better yields are obtainedand the separation of the reaction product is more easily accomplishedwhen utilizing alower alcohol solvent, such as methanol. Also, it issometimes advantageous to heat the reaction mixture to an elevatedtemperature of approximately 70 C. In such instances, however, little ifany advantage is obtained by keepingthe lower to produce sodiumhydroxylamine disulfonate, alcohol reaction mixture at an elevatedtemperawhich is in turn treated with acetone to form acetoxime. Onhydrolysis of the latter with hydrocihloric acid, hydroxylammoniumchloride is prouced.

I have now discovered that hydroxylammonium 2o tory as solvents, butmethanol, being more readily chloride can be prepared in yields of 85per cent and above merely by treating hydroxylammonium sulfate withhydrochloric acid in aqueous, or

aqueous alcoholic solutions. To obtain hydroxyL ture for an extendedlength of time.

There ar several factors to be considered in selecting the lower alcoholsolvent. Methanol, ethanol, propanol, butanol, etc., are all satisfacthereaction product was more easily separated from a methanol reactionsolution than from the ammonium chloride from hydroxylammonium 28 otheralcohol solutions. The amount of alcohol sulfate under such conditions,is entirely contrary to that which one skilled in the art would normallyexpect, since it is known that the solubility of hydroxylammoniumchloride in water is great- .used in the reaction mixture and in thewash respectively should be of the order of one, to one and one-halfequivalents for each equivalent. of hydroxylammonium sulfate. When thenumber of er than that of hydroxylammonium sulfate. For 30 equivalentsof alcohol is increased, there is a deexample, at 25 C. hydroxylammoniumchloride is soluble in water to the extent of 95 grams per 100 grams ofwater, while hydroxylammonium sulfate is soluble in water to the extentof only 64 grams per 100 grams of water.- Notwithstanding pletelyrecovered therefrom.

- found to yield 60 per centof the hydroxylamine crease in the yield ofhydroxylammoni-um chloride, probably due to the fact that greateramounts of hydroxylammonium chloride are dissolved in.

as crystallin hydroxyla nmgnium chlgride and' 40 slightly LESS ofhydrochloric acid is utilized, the

only 3 per cent of. the hydroxylamine as the sulfate.

product obtained is'not entirely hydroxylammonium chloride, but some ofth sulfate is also precipitatedalong with the chloride. In order tosecure satisfactory yields there should be in the able solvent, such asa lower alcohol, at a temreaction mixture an excess of the hydrochloricperature of 0 C. to 85 (7., and preferably from 20 C. to 70 C. Theprecipitation of the hydroxylammonium chloride is facilitated by coolingthe reaction solution, after which the solid acid and preferably thereshould be from one and one-fourth to two equivalents of hydrochloricacid for each equivalent of ,the hydroxylammonium sulfate. For example,a reaction mixture hydroxylammonium chloride may be removed consistingof one equivalent of hydroxylammofrom the reaction solutionby anysuitable means,

portion of a lower alcohol, which may be saved in a State Ofapproximately 99 Per cent Duri ynium sulfate, one and one-halfequivalents of 38 per cent hydrochloric acid, and one equivalent ofmethanol yields-about per cent of the theoretical amount of thehydroxylammonium chloride 85 per cent.

EXAMPLE I.

by the Hydroxylammonium chloride was prepared by heating a mixtureconsisting of 167 parts of 98 per cent hydroxylammonium sulfate, 384parts of 38 per cent hydrochloric acid and 75 parts of isopropyl alcoholin a suitable reaction vessel to a temperature of approximately 70 C.When the reaction appeared to .be complete, the mixture was cooled inice water to a temperature of approximately 18 C. The crystallinehydrbxylarnmonium chloride thus formed was filtered, washed with..60parts of isopropyl alcohol, and dried at approximately 70 C. for 2hours. The product thus obtained corresponded to a yield of 75 per cent.

EXAMPLE 11 One hundred and sixty-seven parts of 98 per centhydroxylammonium sulfate and 384 parts of 38 per cent hydrochloric acidwas heated in a suitable vessel to a temperature of 70 C., with constantagi ion, at which time there was added to the mixture 80 parts ofethanol. The reaction mixture was then cooled as in Example I, and thecrystalline product separated from the reaction mixture, yielding amaterial corresponding to a yield of 73 per cent.

EXAMPLE III The crystalline product obtained in this manner weighed 59.5grams, corresponding to a yield of EXAMPLE IV Tests 12 Equivalentproportions Run HS 1 HOl MeOH in re- M00]?! in Per cent (98%) (38%)action wash yield Y lA 1.0 2.0 1.0 ssh)... 1.0 (fresh)--. 75 l-B 1.0 2.01.0 (wash A) 1.0 (ireshgm 81 l-C. 1.0 2.0 1.0 (wash B). 1.0 (iresh 81 2-1.0 1.5 1.0 iresh) 1.0 fresh 68 2B. 1.0 1.5 1.0 wash A) l 0 fresh 772C.. 1.0 1.5 1.0(washl3)... 10 fresh 77 3A 1.0 1.25 1.0 (lrcsh) l.0iresh) ca 3-B 1.0. 1.25 1.0 (washAfi... 1.0 lreohg. 74 3C 1.0 1.25l.0(washB) 1.0 fresh 73 4A 1,0 1.0" 1.0 (ircsh) l0iresh) 56 4B 1.0 1.0LOEWESIIA) 1.0 fresh). 61 4C 1.0 1.0 1.0 washB)-.- 1.0 (irosh). 65

5-A. 1.0 0.9 1.0 (llesh) 1.0 fresh) 48 5B 1.0 0.9 1.0(washA)... 1.0fresh)" 50 5-C 1.0 0.9 l.0(washB) 1.0 lresh 58 (l-A... 1.0 0.8 1.0 (lresh) 1.0 fresh) 45 6-13....e 1.0 0.8 1.0(Wash A) 1.0 gfresh) 51 6-C 1.00.8 1.0(washB) I 1.0 fresh) 49 1 Hydroxylamine sulfate.

A mixture consisting of 163 parts of 98 per cent 1 hydroxylammoniumsulfate, 384 parts of 38 per cent hydrochloric acid, and 64 parts ofmethanol which had been used asthe wash methanol in Example III, washeated to a temperature of 70 C., after which the heat was cut oil andthe reaction mixture'cooled in ice water to a temperature of 18 C. Thecrystalline product obtained in this manner was filtered, washed withmethanol, and dried at a temperature of 70 C. for two hours. Thehydroxylammonium chloride,

obtained in this manner, corresponded to a yield of 81 per cent.

The following table illustrates in tabular form- Equivalent moportionsHS! no; r3123 g e gg 15 11 (USING as 0 HCl) (USING 33% nor I G'.2s% H011.0 1.5 1.0 1.0 I so 1 y ylammonium sulfat i Hydroxylammonium chloride.

From the foregoing description, it will be apparent to, thoseskilled inthe art that numerous equivalents and modifications of the process de-'scribed herein, exist. For example, instead of utilizinghydroxylammonium sulfate, the acid sulfate may be employed. In suchinstances, it is preferable to employ at least two moles of hydrochloricacid for each mole of hydroxylammonium acid sulfate present. Otherequivalents and modification of my process will be readily recognized bythose skilled in the art.

My invention now having been described, what I claim is:

1. In a process for the production of hydroxylammonium chloride, thestep which comprises reacting aqueous hydrochloric acid withhydroxylammonium sulfate.

2. In a process for the production of hydroxylammonium chloride, thestep which comprises reacting aqueous hydrochloric acid withhydroxylammonium sulfate in the presence of a suitable solvent.

3. Ina process for the production of hydroxylammonium chloride, the stepwhich comprises reacting aqueous hydrochloric acid with 11?-droxylammonium, sulfate in the presence of a 7 lower aliphatic alcohol.

4. In a process, for the production of hydroxyl- Y ammonium chloride,the steps which comprise reacting hydroxylammonium sulfate with aqueoushydrochloric acid, and cooling the resulting reaction mixture to atemperature at which said hydroxylammonium chloride precipitates.

5. In a process for the production of hydroxylammonium chloride, thesteps which comprise reacting aqueous hydrochloric acid :with' hy-'droxylammonium sulfate in the, presence of a lower aliphatic alcohol,and cooling the resulting reaction mixture to a temperature at whichsaid hydroxylammonium chloride precipitates.

6. In a process for the production of hydroxylammonium chloride, thesteps which comprise reacting aqueous hydrochloric acid with hydroxyammonium sulfate in the presence of metha o1, and-cooling the resultingreaction mixture to a temperature at which said hydroxyl-.

ammonium chloride precipitates.

7. In a process for the production of hydroxvlammonium chloride, thestep which comprises reacting aqueous hydrochloric acid withhydroxylammonium sulfate in the. presence of a lower aliphatic alcohol,and at a temperature between 0 and 85 C.

8. In a process for the production of hydroxylammonium chloride, thestep which comprises reacting aqueous hydrochloric acid withhydroxylammonium sulfate in the presence oi a suitable solvent, and at atemperature between 20 and 70 C.

I 9. In aprocess for the production of hydroxylammonium chloride, thesteps which comprise agitating a mixture of aqueous hydrochloric acidand hydroxylammonium sulfate, cooling the resulting'reaction mixture toa temperature at.

which hydroxylammonium chloride precipitates, and separating saidhydroxylammonium. chloride from the reaction mixture.

10. In a process for the production of hydroxylammonium chloride, thesteps which com-

